Gas-generator.



W. MITCHELL.

GAS GENERATOR.

APPLICATION FILED mm: 16,

Patented May 25, 1915.

a M v o W a in one piece-from soine composition. such. as 4 citizen of State of Massachusetts,

Generators, of which the the front part of said body,

" snare Pariarr are.

COM

ORK, N. Y., A CORPORATION OF NEW YO WILLIS MITCHELL, OF M-ALDEN, T'IASS ACHUSETTS, ASSIGN'OR TO WILLIS MITCHELL PANY, INQ, OF NEW Y GAS-GENERATOR.

Specification of Letters Patent.

Patented May 25, 11915.

Application filed June 16, 1913. Serial No. 773,912.

T all whom it may concern:

Be it known that I, VVILLis MITCHELL, a the United States, residing at in the county of Middlesex and have invented cer tain new and useful Improvements in Gas- I following is a speci- Maid en,

cation. I

The chief objects of this provide for regular and of gas and perfectly even discharge thereof; to insure its fixed dry clear character or invention are to quality, and to insure the complete reducthe gas 'PIOClIlClDg eletronv into gas of all merits of the fuel without permitting any of the latter to become burned or baked before generation and consequently accumulated on the walls of the generator.

To these ends I generating reers a continual 1nemploy a steadily tapering tort which necessarily off air cushion and having tubular'connection with the inlet end of said retort as hereinafter more fully set forth and claimed.-

In the accompanying drawings: Figure represents a vertical longitudinal central section of a fuel gas generator embodying my invention, also the front wall of the exterior casing, the pilot burner and the nozzle supplying the same being shown in.

Fig. 2 represents a detail side elevation' of the tapering central tube and core of the said generator, these two parts being side by side,

pilot generpreheating the generator and burner and the ator and burner used for main generator. Fig. 4- represents a sectional view taken onthe line of F 3.

In said drawings the body of the retort or generator 'A is composed of an elongated steel cylinder or shell 1, constituting the outer portion of the part of the body of the generator, and a tubular cylindrical front section 2, screwed thereon and forming provided with a tubular'arm 3 extending obliquely upward and forward and having near its upper end a transverse cylindrical needle-valve casing 4, said parts 2, 3'and 4c being preferably cast brass for exain 'ile. which isabetter-conductor of heat than the cylinder l;.aforesaid.

efficient generation side elesupplied with kerosene or of the burners and that the cooling of the gas in said protruding p"art and nozzle may be prevented; and the said cylinder and section being deta chably screwed together. The forward end of section 2 is screw-tapped to receive a removable screw plug 5, which closes it. lhis plug is recessed in its inner end at 6 to receive the contiguous end of a closed metallic tube 7 fitting tightly therein, so that it may be conveniently withdrawn with said plug. The said tube 7. tapers gradually from its front end, where it is thus attached, to its rear end, which is in the same transverse plane as the rear end of said cylinder 1, though it maybe slightly farther forward as shown. This smaller end is closed by a small plug 8. In effect this tube is a rod acting as a cen tral core to cause the oil to flow in a thin space; since its interior is a closed air space. A solid rod of like diameter would, however, be less satisfactory, as it would absorb more heat in its greater mass and therefore would require more time to make it hot enough throughout for properly heating the oil.

The steel cylinder 1 has a brass lining 9, which will prevent rust or pitholes forming in the steel if dampness should work in with the oil from which the gas is to be generated. Of course this lining 9 will be unnecessary if the outer tube or cylinder 1 be made of brass or any material not easily oxidizable. 'Tlheadvantage of steel in said cylinder 1 is that it will be stronger thickness and less liable to sag when soft ened by intense heat: and for like reasons the closed tube 7 is also preferably made of steel; but a brass tube may be made stron enough, by increasing its thickness or otherwise, to answer my purpose in either case. A cap 10 having its outer end of frusto-conical form screws on the rear end of outer tube or cylinder 1, providing within it"a-t the inlet end gas generator. Said space occupies somewhat more than the rear half of the interior of said cap and is partly cylindrical, partly frusto-conical in form. This inlet end is other fluid hydrocarbon under pressure through an inlet pipe 12 from an oil-tank many other suitable c My chief object in this part of my of the retort or a space 11 invent on is to convert kerosene or other heavy hydrocarbon into a fixed gas for fuel promptly, certainly and cheaply, with no waste of material. but the utmost possible having hitherto yield of fuel gas.

Such a generator or gasifier has long been a desideratum, those in use been generally adapted to convert only the lighter hydrocarbons into fixed gas, or to convert the heavier hydrocarbons into. vapor: and when, it has been possible to convert the heavier hydrocarbons or central tube already referred to,

the. generator. at its inner end mg the inner is being drawn. out as above described. If

clean in like manner cylinder 1.

directly into fixed gas the expense has been too great and the result too unreliable for the procedure to rankas a practical this lining were absent the said brush would the inner face of An annular gasket 14 of suitable material on tube 7 and removable therewith fits in section 52, forming a gas tight seat for the inner end of plug 5 and preventing any leakage at this point, while the parts of the generator are in operative position. Of course after such withdrawal this inner tube is readily cleaned at will.

This brush is removably set into plug 8, so that a larger one, or one that is less worn may be readily substituted at any time. But this brush 18 merely has to deal with dirt or sediment other than carbon, owing to the special construction of my fuel gas generator, which is especially designed to gasify' all of the oil, not allowing any carbon to be deposited in the retort. One of the provisions for especially gua {l 'ng against this evil is the taperingcb struction of the core necessarily provides" a reversely tapering cross-sectional area from rear to front of the retort chamber 15, formed by the thin annular'space or retort chamber 15 between .the core or closed tube 7 and the lining 9.

The last named two parts do not touch at any point, but are much farther apart at their rear ends than at their forward ends,

the diminution of diameter of the core 7 being progressive and very gradual. Consequently the inflowing volume of oil or hydrocarbon is con tinua'lly being forced toward the relief tank by the backward impulses caused by the gas expanding under the in fluence of heat, while the gas is forced onward into a tubular passage of continually narro wing capacity, with necessary reaction,

eddying and oscillation of movement, which pf itself will tend to very eliiciently dislodge which Y any carbon deposits from the.faces of the lining and inner tube, should such take place. To aid such action, these faces should be polished, so that particles of oil may find it very dillicult to adhere.

A means for relieving the back pressure and regulating the oscillations of the oil in the interior of the retort is found in a relief tank or chamber 16, which mounted on and supported by a vertical branch pipe 17, extending up from inlet pipe 12 and containing air, so as to form an elastic cushion or air-spring above forced up into the same. Any excessive resistance in the retort would cause the oil to back up into said chamber ctmiprossing said air in the relief tank 16 and the counteraction of the latter would reinforce the normal pressure on said oil from behind, supplying more oil when the resistance lessens. There is thus an automatic compensating action in this relief tank or chamber which combines to keep up a regular continuous vibration in the retort or gas generating chamber 15. Of course the oil would not be forced up into this tank or clmniber if the volume of that material in pipe 12 beyond it could be more easily driven back to its source, but this is not the case, the hydrocarbon oil being under such pressure from behind that it cannot be packed back upon itself against its own current to more than a very slight degree. Thus without the relief tank the oil would not receive so much motion and would in part bake on the walls. Of course it would be possible to substitute other elastic material for air-for example some other gaseous fluid in this relief chamber.

The needle-valve-casing 4 is provided with a removable conoidal nozzle 18 governed by a needle valve 19 which has a bearing 20 and stuffing-box 21. Said nozzle discharges fixed hydrocarbon gas into the outer end of the burner 2'2, which extends flush with or slightly beyond the front of the main casing .70 of the machine. As the parts 3 and 4 zand the outer portion of section 2 are outside of the said casing and not directly acted on by the heating devices hereinafter described, it becomes desirable to provide for ready conduction of heat to them from the 'directly heated parts of the retort, thereby insuring the thoroughly heated condition of thegas until it is delivered to the burner. This is the reason for the use of a relatively high conducting composition instead of steel in the casting'comprising these parts. The upper end of the bore of arm 3 is closed by a removable screw-plug 23, which provides for easily blowing out and cleansing this bore. No part of the retort is permitted to become red hot, yet the heat, the resistance of the tapering retort and resultant oscillating action are sufiicient to turn kerouny oil which maybe sene oil to a fixed gas discharged as such into the said burner 22. Thisburner-is cylindrical and parallel to said fuel gas generator tion of the retort itself, the latter or retort, being arranged v inbefore described.

the gas having been turned on b I my main fuel gas uniformity ,ulation. TlllS is the the relief chamber 16. B

within the casing and at no great distance therefrom and discharging against the same through the lower rows of very numerous perforations 24, the

y means of an arm 27 corresponding to arm 3 and a nozzle 28 arranged like that here- The burner 25 supplied by said nozzle is first lighted. In this operation the nozzle 28 is .heatedby a torch, y opening the needle valve of said nozzle, and the holes of the match I am not confined thereto, able to the other (1 shown might be substituted with inch in diameter) as shown in area 111 cross-section being preferably a l1ttle greater than the avera e area in cross-secthe tapering space between the iesaid inlet is cals so small a vollime of gas can escape through the needle valve and asthe tapering construction of the ular unless some by proper conservation andregof the rapid as to be indistinguishabl 1, its h being, as

to be removed by the brush tions er temperature t and tests of measurement :The hydrocarbon the heat of 'on or before reaching two thirds of the length of the tapering retort l5 and its expansion, coacting with the liq-' the gaseous'rea series of oscilsistancebefore it, produces lations, which prevents the oil from baking or urnmg on the inner walls of the retort.

Nevertheless, the current flows on with in creasing resistance, owing to the steady and the any particular point of the length of the retort by the .action of such relief chamber, until atthe discharge end of the retort they are so exceedingly e, making a practically unchanging condit1on of the outand will be steadily and without perturbation,

except the. oscilla tions ending in a practically efficiently operative condition, the oscillations having become so frequent that th though they did not exist. The d rapidity, subject to heat determined in degree by such outflow, will insure thorough transformation of the oil to a permanently fixed vent a'll practically all such form and carry such oscillating. but advancing current, until they are reduced-to gas like the 'otl'lervolatile material; No carbonin solid form is left or otherwise.

gaseous a gas forward with the Besides mec'l anical'liquid oscillations above; I

described, there mustnecessarily be oscilla- 0 some extent as the moves nearer tot-he parts of v the generator or' retort, where the. accu-- mulated heat has the greatest effect or back toward and beyond the inlet, Where it is least and where the entering oil is cooler than the vapor or gas produced therefrom: although the conductivity of the steel tube 1 and the other metal parts and the still greater conductivity of the section2, as well as the action of the atmospheric air on the latter will modify this action and tend to movement of the hydrocarbon,

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A gas generator provided with an elongated retort chamber of thin annular tapering'form, in combination with means for discl'iarging heat directly on the exterior of said generator.

2. In a gas generator, a tapering core and a cylinder external thereto, providing between them a tapering annularretort chamber adapted to receive fluid fuel at one end and discharge the same as fixed other, in combination with a burner arranged to discharge against thesaid cylinder.

3. In a gas generator, a pair horizontal parts, forming between them a retort chainber of thin annular form in cross section, which tapers from the receiving end to the discharging end, and a burner arrangeil to dircctJia-nie against the-exterior of the outer one of said parts.

4. An elongated, tapering, horizontal gas retort chamber, in combination with an inlet pipe supplying the same at the larger end, a branch pipe extending from said inlet pipe out of the line of flow of the fuel to said chamber and a regulating ,ank in which said branch pipe ends and which forms an air cushion to aid the operation of said retort chamber.

5. A gas generator provided with a gas retort chamber, an inlet pipe and a regulating tank forming an air cushion connected to said pipe, said tank being supported at a higher level than the said retort chamber and permanently in communication therewith. v

6. In a gas generator, a tapering retort chan'iber, an inlet pipe supplying thesame at the larger end of said chamber, a branch pipe extending vertically upward from said inlet pipe and a relief chamber supported by said branch pipe andreceivingthe upper connected to said branch pipe,

the

gas at the of elongated end of the latter in its bottom, the upper part of said'air chamber providing a cushion of inclosed air.

7. A tapering retort chamber, in combination with a nozzle "connected to its smaller end, aninlet pipe discharging into its larger end, a branch pipe from said inlet pipe, and a relief tank containing an air cushion and but out of the line of flow of the fuel.

8. In a gas generator, an internally lined elongated outer shell and a tapering elongated core within the samearranged to form between them a thin retort chamber annular in cross section and tapering in the direction of flow, an inlet pipe supplying the larger end of said retort, a branch pipe extending therefrom, and a relief tank connected to said branch pipe, but out of the line of flow of the fuel-to said retort.

9. A retort chamber tapering in the direction of the line of How, in combination with an inlet pipe, a branch pipe, and compressible and expansible branch pipe out of the main line of flow, but arranged to receive and store back pressure of said retort chamber and return the same to equaliv the discharge of said retort chamber.

10. In combination with a cylinder constituting a part of the outer body of a gas generator, a. separable section attached thereto and forming the front part of said body, a casing, through which the said front protrudes, and a removable core arranged within the said cylinder, the said cylinder and core leaving an annular elongated tapering retort between them.

11. In combination with a shell constituting the main part ,(if the outer body of a gas generator, a section attached thereto as the front part of said body, a casing, through which the said section protrudes and a core within said shell, the space between said core and shell constituting a tapering retort chamber of thin annular form in cross-section.

12. A gas generator having a detachable forward section comprising an inclined tubular arm and an integral needle-valve casing and provided also with an elongated cylinder extending rearward fromsaid secmeans connected with said ill) core being shaped to presenta tapering rctort chamber between them, said retort chamber'having an inlet at its larger end.

13. In combinationwith a tubular part constituting the greater portion of the body of a gas generator, a section screwed thereon in forward extension of said ,body, and provided with discharging devices and screwtapped at its front end, a screw plug turned into the said screw-tapped end and provided v with a-recess at its inner end, and a core which fits at its proximate end into said reeess and which is arranged within said tubular part, being of less diameter than the interior diameter of the latter, to form a re tort chamber between them.

14-. In combination with a tubular part of a gas generator and a core of less diameter within said part, leaving a space as a retort chamber between them, a nozzle and connections for discharging the gas generated in said retort chamber and a cap covering the inlet end of said retort chamber provided with an opening for the inlet of fuel, said cap providing a space or chamber between said opening and the inlet end of said retort.

15. In combination with a main generator and a pilot generator, a pilot burner supplied by said pilot generator and arranged below said generators to discharge flame continuously and permanently on both of them, and a main burner supplied by the main generator and arranged parallel to and above the latter to discharge flame on the outer shell of the said main generator.

16. In combination with a cylindrical horizontal gas generator, a pilot burner and main burner, all three of these devices being cylindrical and horizontal, the said generator being arranged above one of the said burners and below the other and receiving 30 the converging jets of flame on its outer shell.

17. In combination with two burners, a gas generator which supplies one of them and is arranged to receive the jets of flame from both of them 011 its exterior, one of the said burners being above said generator and the other burner being below it.

18. In combination with two burners, two gas generators, one of said burners being arranged to discharge flame on both generators, both burners being arranged to discharge on one of the generators from above and below and the generators respectively supplying the burners individually.

In testimony whereof, I have signed my name to this specification in the presence of two subscribing witnesses.

WILLIS MITCHEL Witnesses MADALINE B. CRAWFORD, JACOB SPEAK. 

